Lapping machine



June 27, 1933.

A. E. ROBINSON ET AL LAPFING MACHINE Filed July 2, 1932 5 Sheets-Sheet l June 27, 1933. E. ROBINSON ET AL 1,916,118

LAPPING MACHINE Filed July 2, 1952 3 Sheets-Sheet 2 June 27, 1933. A. EROBINSON ET AL 1,916,113

LAPPING MACHINE Filed July 2, 1952 s Sheets-Sheet s "'IIIIIIIII Patented June 27, 19 33 UNITED STATES QFFEE ALBERT ROBINSON, or CINCINNATI, nn w rin nn e. noELscnnR, or NORWOOD, OHIO, AssIeno i-s r r m AMERICAN r00; worms COMPANY, or CINCINNATI, OHIO,

n GOBBORATION or onto errme Application filed July 2,

()ur invention relates to lapping machines for lapping meshing gears, and has for lts object the provision of novel means for qualifying lapping engagement between the teeth of gears being lapped.

it is the object of our invention further to provide novel means for adjusting the angular relations between rotative members in the train of mechanism between gears; and, further, to provide resilient driving means between said rotative members.

it is the object of our invention further to provide novel means for adjusting the force of angular impact in both directions between meshing gears being lapped, whereby to 1mpose forceful Contact between the respective of the teeth of the meshing gears; furr, to provide novel means for causing relien e of engagement between the respec- -ve sides of the teeth of meshing gears being lapped; and, further, to provide novel leans whereby a preload is imposed between ing gears being lapped. re invention will be further readily unood from the following description and and from the drawings, in which sid '. 1 is a plan view of my improved de- 2 is an end elevation .of the same.

3 is an axial section of the qualifying taken on a vertical plane through Fig. n partly broken away.

e is a plan View of the gage for the head, laid out in plane, and partly broken away.

Fig. is a horizontal axial section of my improved device, taken on the line 5-5 of F 2. 14) l ig. 6 is a side elevation of the same, partl biiL-EQQ away, and partly in vertical sect on on the line 66 of Fig. 1.

F is a cross-section of a detail of my mpbved device, taken in the plane of the ins '"7 of Fig. 5.

MACHINE 1932. Serial No. 620,802.

Fig. 10 is a cross-section ,of a detail of the same, taken in the plane of the irregular line The present invention is an elaboration of the inventions shown, described and claimed in the ,copending applications for Letters Patent on improvements in lapping machines, filed in the United States Patent .Ofi'ice by Albert E. Robinson, one of the oint applicants herein, April 13, 1981, as Serial No. 529,735, and Serial No. 529,736.

The machine comprises a frame 11, which supports an electric motor 12, which is preferably a reversible motor. A housing'13 is preferably fixed to the frame, as by bolts 14. This housing has a drive shaft therein, extending lengthwise of the frame, and journaled in bearings 16. A pulley 17 is fixed to this drive shaft, a belt 18 being received thereover and over a pulley 19 on the motor shaft 20.

An arbor 21 extends crosswiseof the frame and is rotatable in bearings 22, 23, in the housing (Fig. It is exemplified as comprising a sleeve 25 provided with a bore 26 having a tapered end forming a socket 27, receiving the tapered end 28 of a spindle 29. A screw rod 31 is in the bore and has threaded connection 32 with the inner end of the spindle, and a head 33 received against the end of the sleeve, for drawing the tapered end of the spindle into its tapered socket and fixing the spindle axially in the sleeve and permitting ready removal of the same.

Guideways .85 extend lengthwise of the frame. A slide 86 is adjustable on said guideways toward and from the housing 13, accomplished by means of a screw-rod 37, journaled and held endwise in a bearing 38 at the end of the frame, and having threaded connection with a nut 39 fixed to the slide by a bolt 40, forming a micrometer adjustmentfor the slide (Fig. 6).

The slide supports an arbor 11, rotatable in bearings 42, 43, in a housing 44 on the slide. This arbor comprises a sleeve 45 provided with a bore 46 having a tapered socket 4:7 at one end, in whichthe tapered end 48 of a spindle49 is received. A screw-rod 50 has threaded connection 51 with the tapered end of said spindle, and a head 52 received against the end of the sleeve. This arrangement draws the spindle firmly into the sleeve for centering the spindle and permitting its removal.

Master gears 55, 56, are received in meshing relation about one of the ends of the arbors, and gears to be lapped 57, 58, are received in meshing relation over spindles at the other of the ends of said arbors. The gears rotate with their respective arbors, and are centered ibn suitable manner about their respective arors.

Thus the master gear 55 is received about a hub 61 and has key connection 62 with said hub so as to rotate therewith (Fig. 5). The hub is provided with an annular shoulder 63, a washer 64 being located between said annular shoulder and the gear 55. A washer 65 is received at the outside of the gear, a nut 66 being threaded over the threaded end 67 of the hub for clamping the master gear to the hub. Hubs of different diameters may be employed for master gears having different sized holes, or filling sleeves maybe employed for centering the gear upon the hub.

The master gear 56 is received about a bushing 71 011 the sleeve of the arbor 41. The bushing is provided with a flange 72. The bushing has key connection 73 with the sleeve of the arbor, and the gear has key connection 7 4 with the bushing. A washer 7 5 is received about the sleeve at the outer end of the bushing, a nut 76 being threaded over the threaded end 77 of said sleeve for clamping the parts toward an annular shoulder 7 8 on the sleeve and clamping the parts to the sleeve. Bushings of different diameters may be provided for gears having holes of different diameters. Spindles 29, 49 having gear supporting portions of different diameters may be employed. The gear to be lapped 57 has key connection 79 with the spindle 29, and the gear to be lapped 58 has key connection 80 with the spindle 49. Bushings similar to the bushing 71 may be received about the hub 61 and the spindles 29, 49, for accommodating gears having holes of different diameters.

Filling collars 81, 82, of different lengths are received over the respective spindles, washers 83, 84, being at the outer ends of said respective sets of collars, and nuts 85, 86, are threaded to the outer ends of the re spective spindles for clamping the gears to be lapped and the collars between flanges 87.

88, on therespective spindles and said nuts and washers. A plurality of gears to be lapped may be located side by side on the respective spindles.

A bevel gear 91 is fixed to the drive shaft 15 (Fig. 5). This bevel gear meshes with a bevel gear 92 mounted about the sleeve 25, the bevel gear having key connection 93 with the sleeve. The bearings 22, 23, are shown as ball bearings, the outer raceways of which are received in annular rabbets 94, 95, in the housing 13, being clamped in place by caps 96, 97, fixed to the outer ends of said housing. The inner raceways of these ball bearings are received about the outer circumference of the sleeve 25. The outer end of the inner raceway of the ball bearing 23 is received against a shoulder 98 on the sleeve. The inner raceways of the ball bearings 22, 23, are held in spaced relation by the bevel gear 92 and a collar A collar 100 is received about saidsleeve at the outer end of the inner raceway of the ball bearing 22, nut 101 being threaded over the sleeve for clamping the collars and the inner raceways toward the shoulder 98.

The arbor 41 is rotatable in the bearings 42, 43, the outer raceways of said bearings being located in annular rabbets 105, 106, in the housing 44, caps 10?, 108 being secured to said housing and clamped against said outer raceways.

A gear 110 is located about the sleeve and has key connection 111 therewith. The inner raceways of the ball bearings 42, 4 are spaced apart by means of said gear and a collar 112. A collr 113 is at the outside of the inner raceway of the ball bearing 42, a nut 114 being threaded over the threaded portion 115 of said sleeve for clamping said lastnamed collars, inner raceways and gear toward an annular shoulder 116 of said sleeve.

Lubricant shields 117, 118, are received about the sleeves 25, 45, between shoulders 119, 120 thereon and the respective gears to be meshed.

Endwise reciprocation may be imparted to the arbor 41 for cai g endwise movement between the respective of the sets of gears, so as to cause lapp action between the teeth of the gears being lapped across the widths of said teeth (Figs. 1, 2, 5 and 6). For this purpose the housing 44 i mounted on a cross slide on the slide 36. The sl de 36 is provided with a guide 126 with which :1 guideway 12! on the cross slide coacts.

The housing 44 is provided with bearings 13 1, 132, 133, in which shafts 134, 135, 136 rotate. The shaft 134 has a bevel pinion 137 thereon wh ch meshes with the bevel ear 110. The shaft 134 is also provioed with a pinion 138. The shaft is provided with a gear 139 meshing with the pinion 13S. and with a pinion 140 which meshes with a gear 141 on the shaft 136. The shaft 136 is provided with a crank 142.

A bearing 140 of a link 146 is received about said crank at one end of said link. The other end of said link has a bearing 14'? about a pin 148 in a stand 149 fixed to the slide 36. This construction converts the rotary motion of the crank into reciprocating linear movements of the cross slide ano imparts cndwise movements to the arbor 41 and the gears mounted thereon.

Means are provided for adjusting the angular relations between the gears being lapped on the respective arbors, and means are also provided for causing resilient coaction between the faces of the teeth of the respective gears being lapped, and these respective means are shown so arranged that angular adjustments may be effected toward the respective sides of similar radial planes of the gears being lapped, and that resiliently yielding lapping contacts may be made between the respective sides of the teeth of the meshing gears being lapped.

A head 151 is provided for effecting these operations (Figs. 8 and 5). The head comprises the relatively movable sections 152, 153, one of which is fixed with relation to one of the master gears and the other of which is fixed with relation to one of the gears being lapped. There are resiliently yielding means between the two sections for permitting resilient yielding between the gears being lapped, and one of the sections is also provided with adjusting means for causing preponderance of pressure at the respective sides of the teeth of the gears being lapped. These latter adjusting means are shown on the section 152.

More particularly described the section 152 comprises an outer member 154, shown as a ring or plate, in which the hub 61 is located, the hub being extended outwardly to form a support for the master gear v55. The hub is centered and is held endwise on a reduced end 155 of the sleeve of the arbor 21.

The hub is provided with a worm wheel 161 with which a worm 162 meshes (Figs. 3 and 8). This worm is on a worm shaft 163, journaled in bearings 164, 165, of the outer ring portion 154 of the section 152 which surrounds the worm wheel. The worm shaft is held endwise in said bearings by an annular shoulder 166 and a washer 167 and nut 168 threaded over the threaded end of the worm; shaft, and located at the respective ends of the bearing 165. The worm shaft is provided with suitable formation for rotating the same, shown as a square head 169 for receiving a suitable wrench.

The head and the Washer and nut are respectively in recesses 17 0, 171, in said outer ring or member. Adjustment of the worm shaft adjusts the angular relation of the hub 61 011 which the worm wheel is located and the ring member or outer portion of the section 152 on which the worm is located. The adjusting means adjusts the angular relation of the gear to be lapped and its arbor with relation to the master gear 55.

The section 153 comprises a housing 17 5 mounted on a step 17 6 of the arbor between shoulders 177, 17 8 on said arbor, locating the housing between the shoulder 17 8 and the section 152 in such. manner that relative rotation may readily take place between the then hardened.

sections 158, 152. The housing has key connection 17 9 with the arbor.

The housing is provided with an annular chamber 181 which is closed by an end plate 182 positioned by annular shoulders 183,184, in the respective annular walls of said chamber. Said cover and the bottom wall of the chamber are respectively provided with arcuate slots 185, 186, through which bolts 187, 188 are received into threaded holes 189, 190 in the outer ring member 154 of the section 152. The bolts are arranged to be threaded into their threaded holes to suificient extent to hold the parts in axial directions and at the same time permit relative rotations between the sections 152, 158. The bolts are preferably clamped in adjusted positions by plugs 191 received in threaded holes 192 in the outer member 15st and clamped against the respective bolts by screws 198 in said respective threaded holes.

Levers 195, 196, are pivoted on pivot pins 197, 198, shown as shoulder pins whose ends are located in holes in the respective walls of the chamber 181, said levers being provided with toes 199, 200, which are arranged to bear against the bolt 18'? (Figs. 7, 9 and 10). The levers are urged toward said bolt by springs 201, 202 received about rods 208, 204: having rounded heads 205, 206 received in seats 207, 208 in the heels 209, 210 of said levers. Bearings 215, 216 have pin journals 217, 218 journaled in holes in the respective walls of the chamber 181, and are provided with slide holes 219, 220 in which the rods 208, 204 have axial movements.

In operation, rotation is imparted to the drive shaft. direction or alternately in opposite directions, as may be desired or the character of the work requires. The master gears 55, 56. are provided with teeth of proper form, pitch and depth for determining the form, pitch and depth of the teeth of the gears to be lapped by the lapping operation.

The gears to be lapped usually have their teeth out or formed slightly oversize and are The hardening of the gears is likely to cause change in the form of the gears or some or all of the teeth, and the object of the lapping is to reduceand reshape the teeth to their prop-er forms and sizes. The hardened gears may also have high spots on their teeth, or the teeth or parts or the same may be warped or their surfaces be rough or uneven, these objectionable conditions being corrected by the lapping.

The lapping is performed by causing meshing relation between the rotating gears being lapped and supplying a lapping compound, which may be a mixture of powdered carborundum and grease, either manually or automatically to their teeth in suitable manner.

When uneven or untrue parts of the teeth This rotation may be in either being lapped engage each other in the lapping operation, a momentary excess resilient resistance takes place between the gears for aiding in more quickly reducing such uneven or untrue parts.

Our improved device provides means whereby pressure or a preload is exerted between the engaging faces or proximate sides of the teeth of the gears being lapped, for speedily reducing said engaging faces or proximate sides to desired form and size, and whereby such pressure is exerted selectively toward the respective sides of the respective teeth in order to reduce both sides of all of the teeth to desired form and size, and whereby such pressure or preload is varied according to the sizes of the teeth of the gears being lapped, so as to expedite the lappin Assuming that the gears being lapped have been adjusted toward each other to full extent permitted by the unlapped condition of their teeth, rotation of the worm 162 in one or the other direction causes rotation of the outer member or ring 154; of the section 152 of the head 151 with relation to the inner member or hub 61 of said section 152, and causes planetary shifting of the bolt or contact member 187, which reacts upon the respective levers 195, 196, causing compression of the spring acting on that lever toward which said bolt or contact member has been moved, and thereby causes preponderant pressure, or, it may be termed, a preload, upon the coacting sides of the teeth of the gears being lapped which by said adjustment have been urged into more intimate contact.

The adjustments between the outer member 154C of the section 152 and the section 153 of the head 151 are preferably made to definite extents, dependent on the sizes of the teeth of the gears, the extent of adjustment increasing with said sizes, for instance in accordance with the graduations 221, 222 of a scale 223. These graduations are placed on two of the relatively shiftable parts of the head 151, being shown on the outer peripheries of the respective sections 152, 153.

The graduations at the respective sides of the zero lines indicate desired relations between the shiftable parts of the head when opposite faces of gears having teeth of different diametral pitches are being lapped. The lines denoting corresponding diametral pitches in the respective graduations on the respective sections of the head are brought in line with each other in this adjustment, it being assumed that the gears being lapped have been adjusted toward each other to full extent.

Thus when lapping gears having teeth of five diametral pitch, the lines of the numerals 5 at one side of zero are brought in line with each other, and when lapping gears having teeth of sixteen diametral pitch, the

lines of the numerals 16 in the respective graduations at one side of zero are brought in line with each other.

The markings of the graduations are repeated at opposite sides of the zero lines in reverse order, indicating an advanced relation in each direction between the anchor member or bolt 187 and the respective levers 195, 196, indicating an abnormal pressure or preload in one direction or in the other upon the teeth of the gears being lapped, reversals in directions of rotations of the gears being also caused when graduations at opposite sides of the zero lines are used.

The gears on the arbor 11 are fed toward the gears on the arbor 21, during the lapping operation, by adjustment of the slide 36 by means of the micrometer screw 37. The lapping is preferably continued until the full depth and form of the teeth being lapped is obtained.

Having thus fully described our invention, what we claim as new, and desire to secure by Letters Patent, is:

1. In a gear lapping machine, the combination of a pair of arbors, means for mounting meshing master gears about the axes of rotation of said arbors, means for mounting meshing gears to be lapped about the axes of rotation of said arbors, arranged to form rotative connections between said gears including a pair of rotative members, means for adjusting the angular relations between said rotative members, and resilient resistant means acting on the latter.

2. In a gear lapping machine, the combination of meshing master gears, meshing gears to be lapped, and driving means between said gears including resilient means, coacting rotative members, and means for adjusting the angular relations between said coacting rotative members resisted by said resilient means.

3. In a gear lapping machine, the combination of meshing master gears, meshing gears to be lapped, and driving means between said gears including resilient means, eoacting rotative members, means for adjusting the angular relations between said coacting rotative members resisted by said resilient means, and means determining the extents of said adjustments according to the diametral pitches of the teeth of said gears.

4. In a gear lapping machine, the combination of meshing master gears, meshing gears to be lapped, rotative mounting means for said gears, rotative members between said mounting means, oppositely acting resilient means between said rotative members, anchoring means on said respective rotative members for said resilient means, and means for adjusting the angular relation between sa d anchoring means.

5. In a preloading device for lapping machines of the character described, the combination of a mounting for a master gear, a mounting for a gear to be lapped, an anchor member between said mountings, said anchor member comprising an anchor, means for adjusting the angular relation between said anchor member and one of said mountings, and spring means between said anchor and the other of said mountings.

6. In a gear lapping machine of the character described, the combination with meshing master gears and meshing gears to be lapped, of a mounting for a master gear and a mounting for a gear to be lapped, comprising a plurality of rotative members, one of which is angularly held with relation to said master gear and the other of which is angularly held with relation to said gear to be lapped, a third rotative member, angular adjusting means between said third rotative member and one of said first-named rotative members, and spring resistance means between said third rotative member and the other of said first-named rotative members.

7. In a preloading device of the character described, the combination of a pair of gear mountings, an anchor therebetween, means for angularly adjusting said anchor with relation to one of said gear mountings, and resistant spring means between said anchor and the other of said gear mountings.

8. In a preloading device of the character described, the combination of a pair of gear mountings, an anchor and spring resistant means therefor forming oppositely urging parts between said gear mountings, supports for said parts, and means for angularly adjusting one of said supports with relation to one of said gear mountings.

9. In a preloading device of the character described, the combination of a pair of gear mountings, an anchor and spring resistant means therefor forming oppositely urging parts between said gear mountings, supports for said parts, means for angularly adjusting one of said supports with relation to one of said gear mountings and means determining the extents of said angular adjustments according to the diametral pitches of the teeth of the gears.

10. In a preloading device of the character described, the combination of a pair of gear mountings, a preloading head therebetween comprising a pair of rotative members, one for each of said mountings, anintermediate rotative member, means for angularly adjusting said intermediate rotative member with relation to one of said pair of rotative members, an anchor on one of said last-named members, and oppositely acting parts coacting with said anchor and sprmg means therefor on the other of said lastnamed members.

11. In a preloading device of the character described, the combination of a pair of gear mountings and a preloading head therebetween comprising three relatively rotary members two of which are anchored to said respective gear mountings and the third of which has adjusting connection and coactive rotary resilient connection respectively with said two of said members.

12. In a preloading device of the character described, the combination of a pair of gear mountings and a preloading head therebetween comprising rotative members, an anchor on one of said rotative members, oppositely acting levers acting oppositely on said anchor, said levers pivoted to another of said rotative members, spring means on said other of said rotative members resistingly acting on said levers, and angular adjusting means between one of said last-named rotative members and a third one of said rotative members.

13. In a preloading device of the character described, the combination of a pair of gear mountings, a preloading head therebetween comprising a housing, oppositely presented levers pivoted in said housing, springs in said housing acting resistingly on said respective levers, an anchor between said levers,

said levers and said anchor forming oppositely resistant members, and angular adjusting means between one of said oppositely resistant members and said housing.

In testimony whereof, we have hereunto signed our names.

ALBERT n. ROBINSON. WILLIAM G. HOELSCHER. 

